In a large sauce pot, melt butter...add the onions and cook until soft...add garlic...saute just until you smell garlic...add the jalapenos...add can of tomatos... let simmer for a couple minutes...add Velveeta chunks and milk...(have heat on low at this point) stir occasionally until cheese has melted completely (you may want to add more milk, depending on thickness)

The Jalapenos may be substituted with 3 cans of the 4oz Green Chiles if you'd like.....

This can be made a couple days in advance and keep in the fridge!!!! (you will want to re-heat on low, and add alil milk to the bottom of the pot before you put Queso in)
I serve mine in the Crockpot (on lowest setting) to keep nice and warm for the tortilla chips!

Green chili chicken enchiladas are my favorite and they are soo easy. Line a square casserole dish with flour tortillas then layer chicken, green chilis, cheese and sour cream. I layer 3 high. Spice it up any way you like . Pop in oven for 20 mins.

Are you by chance going to be using chaffing dishes or any other type of method to keep the food warm? The reason being is because a lot of Mexican/Southwestern dishes taste horrible when they're cold (espcially the dishes that most people are familiar with), unless they're supposed to be served that way. If you are going to be using something to keep the food hot, then that will give you a lot more options in terms of what to serve.

As a child, we would visit Family in Florida, and instead of asking "Are we there YET?".....we would ask....Are We "OUTTA TEXAS YET?????" (from El Paso Texas it's a S-T-R-E-T-C-H)

This would be a really fun and memorable thing to do for all the guests after a Southwest party!....
Everyone can make the Sopapillas together!
Have a Sopapilla Bar with all kinds of Goodies to induldge atop!!!
I know you said Yakuta, that 50 or so would be attending...so these might be a little too labor intensive for this Fiesta, unless your are the Lady that just won the Lotto for the "second time" they were talking about in the News, and you already have a "BIG KITCHEN!"

LOL! but, Jakath just gave me some really great ideas for the next Fiesta!!!

Wow you guys have given me so many ideas. Ironchef you bring up a good point on keeping items warm but here is my plan.

When people first come in and get acquainted we will leave some salsa's and chips out along with punch. People will munch and chat and wait until the guest of honor arrives. After that we will serve lunch. I will make two trays of enchiladas and fajitas. I will remove one tray at a time so that the others stay warm. People can help themselves with one and being the fact that there are 50 or so folks, I doubt I will have many leftovers. The fajita's will not be sizzling but should taste fine warm with all sorts of condiments. The rice should be fine slightly warm not piping hot as well. Finally I will have corn bread again which will be slightly warm.

I know why I hate having one oven now. It's impossible to fit everything in it. I do however have a large warming drawer where I can place dishes in and out of for quick warming.

I personally like hot food at parties and am not a huge fan of all cold cuts and room temperature stuff even in the summer months. I hope I can pull it off.